#include<iostream>
#include<fstream>
#include<string.h>
using namespace std;
int lit(char c)
{
if('a'<=c and c<='z' or 'A'<=c and c<='Z')return 1;
return 0;
}
int main ()
{
ifstream f("text.in");
ofstream g("text.out");
char s,z;
int nrcuv=0,l=0;
z=NULL;
while(f.get(s))
{
if(lit(s))++l;
if(lit(s) and !lit(z))++nrcuv;
z=s;
}
g<<l/nrcuv<<"\n";
f.close();
g.close();
return 0;
}